package com.atguigu.gulimall.product.service.impl;

import org.springframework.stereotype.Service;

import java.util.Comparator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import org.springframework.transaction.annotation.Transactional;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {

        //1.查询所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);

        //2.组装父子结构

        //2.1找到所有的一级分类
        List<CategoryEntity> collect = entities.stream().
                filter(categoryEntity -> categoryEntity.getParentCid() == 0).
                map(categoryEntity -> {
                    categoryEntity.setChildren(getChildrens(categoryEntity,entities));
                    return categoryEntity;
                }).
                sorted(Comparator.comparingInt(CategoryEntity::getSort)).
                collect(Collectors.toList());
        return collect;
    }

    /**
     * 递归查找所有子菜单
     * @param upMenu
     * @param all
     * @return
     */
    private List<CategoryEntity> getChildrens(CategoryEntity upMenu,List<CategoryEntity> all){
        List<CategoryEntity> collect = all.stream().
                filter(categoryEntity -> upMenu.getCatId().equals(categoryEntity.getParentCid())).
                map(categoryEntity -> {
                    categoryEntity.setChildren(getChildrens(categoryEntity, all));
                    return categoryEntity;
                }).
                sorted(Comparator.comparingInt(o -> (o.getSort() == null ? 0 : o.getSort()))).
                collect(Collectors.toList());
        return collect;
    }

    /**
     * 1.业务层逻辑处理,检查当前要删除的菜单id是否被别的地方引用
     * 2.如果有引用则不能被删除
     * @param catIds
     */
    @Override
    public void removeMenuByIds(List<Long> catIds) {
        //TODO 检查当前要删除的菜单id是否被别的地方引用
        baseMapper.deleteBatchIds(catIds);
    }
}